Navy engineers had a banner day on Thursday, with two weapons tests breaking world records--loudly.

Advertisement - Continue Reading Below

Demonstrating the power of an extreme machine that PM got an exclusive first look at last year, engineers fired a seven-pound slug from an electromagnetic railgun at a record power level of 10 megajoules (check out video below). That kind of muzzle energy should be enough to pulverize land and sea targets at long ranges.

The previous railgun power record hovered around nine megajoules. The electric system is meant to replace Navy warship's 5-in. guns.

Later last night, at the High Speed Test Track at Holloman Air Force Base in New Mexico, a classified Navy test rocketed a payload across a track at 6589 mph--136 mph faster that the existing land speed record for anything on tracks.

The secret payload traveled a distance of 3.61 miles in about six seconds on three sleds. Each sled ignited in stages to propel the cargo down the track. A helium tent enclosed nearly three miles of the 10-mile track in order to reduce the aerodynamic heating and drag on the payload.

Despite our earlier speculation, no one is saying what it was that traveled so fast. Navy sources did admit that, on top of the multiple sonic booms heard in the desert, the payload itself detonated at the end of the track.

A Part of Hearst Digital Media
Popular Mechanics participates in various affiliate marketing programs, which means we may get paid commissions on editorially chosen products purchased through our links to retailer sites.